Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964787AbXHGUue (ORCPT ); Tue, 7 Aug 2007 16:50:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935152AbXHGUrh (ORCPT ); Tue, 7 Aug 2007 16:47:37 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:51421 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935319AbXHGUrg (ORCPT ); Tue, 7 Aug 2007 16:47:36 -0400 Date: Tue, 7 Aug 2007 13:43:52 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, bunk@stusta.de, "David S. Miller" Subject: [2.6.22.2 review 12/84] Fix error queue socket lookup in ipv6 Message-ID: <20070807204352.GM23028@kroah.com> References: <20070807204034.882009319@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="fix-error-queue-socket-lookup-in-ipv6.patch" In-Reply-To: <20070807204157.GA23028@kroah.com> User-Agent: Mutt/1.5.15 (2007-04-06) X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2765 Lines: 71 From: Dmitry Butskoy [IPV6]: MSG_ERRQUEUE messages do not pass to connected raw sockets From: Dmitry Butskoy Taken from http://bugzilla.kernel.org/show_bug.cgi?id=8747 Problem Description: It is related to the possibility to obtain MSG_ERRQUEUE messages from the udp and raw sockets, both connected and unconnected. There is a little typo in net/ipv6/icmp.c code, which prevents such messages to be delivered to the errqueue of the correspond raw socket, when the socket is CONNECTED. The typo is due to swap of local/remote addresses. Consider __raw_v6_lookup() function from net/ipv6/raw.c. When a raw socket is looked up usual way, it is something like: sk = __raw_v6_lookup(sk, nexthdr, daddr, saddr, IP6CB(skb)->iif); where "daddr" is a destination address of the incoming packet (IOW our local address), "saddr" is a source address of the incoming packet (the remote end). But when the raw socket is looked up for some icmp error report, in net/ipv6/icmp.c:icmpv6_notify() , daddr/saddr are obtained from the echoed fragment of the "bad" packet, i.e. "daddr" is the original destination address of that packet, "saddr" is our local address. Hence, for icmpv6_notify() must use "saddr, daddr" in its arguments, not "daddr, saddr" ... Steps to reproduce: Create some raw socket, connect it to an address, and cause some error situation: f.e. set ttl=1 where the remote address is more than 1 hop to reach. Set IPV6_RECVERR . Then send something and wait for the error (f.e. poll() with POLLERR|POLLIN). You should receive "time exceeded" icmp message (because of "ttl=1"), but the socket do not receive it. If you do not connect your raw socket, you will receive MSG_ERRQUEUE successfully. (The reason is that for unconnected socket there are no actual checks for local/remote addresses). Signed-off-by: Andrew Morton Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/icmp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -604,7 +604,7 @@ static void icmpv6_notify(struct sk_buff read_lock(&raw_v6_lock); if ((sk = sk_head(&raw_v6_htable[hash])) != NULL) { - while((sk = __raw_v6_lookup(sk, nexthdr, daddr, saddr, + while ((sk = __raw_v6_lookup(sk, nexthdr, saddr, daddr, IP6CB(skb)->iif))) { rawv6_err(sk, skb, NULL, type, code, inner_offset, info); sk = sk_next(sk); -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/